Get drawn polygon

I draw a polygon on the map. I set MapBox.ActiveTool =
SharpMap.Forms.MapBox.Tools.DrawPolygon and handle map's double-click event
to catch when polygon drawing has been finished. My question is: how to get the drawn polygon as a geometry? Is there any straightforward way?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using GeoAPI.Geometries;
using SharpMap.Layers;
using SharpMap.Data;
using SharpMap.Styles;
using SharpMap.Rendering.Thematics;
using BruTile.Web;
using SharpMap.Data.Providers;

if DotSpatialProjections

using GeometryTransform = DotSpatial.Projections.GeometryTransform;
using WinFormSamples.Samples;